New Zealand's Tallest Mountain Shrinks by 100 Feet

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New Zealand's stunning Aoraki/Mount Cook, the country's tallest
peak, is officially 98 feet (30 meters) shorter than previously
thought, researchers with the University of Otago announced today
(Jan. 15).

While currently officially listed as 12,316 feet (3,754 meters)
tall, GPS data from an Otago-led climbing expedition reveal that
Aoraki/Mount Cook is actually only 12,217 feet (3,724 m) high,
the scientists said today.

Capped by a brilliant crown of snow and ice, Aoraki/Mount Cook
towers above the Southern Alps on New Zealand's South Island. On
Dec. 14, 1991, the peak was 12,349 feet (3,764 m) tall when a
massive rock and ice
avalanche cut 33 feet (10 m) off its top.

Since the avalanche, the ice crown has continued to collapse, the
University of Otago scientists recently discovered.

"When it broke, the top of the ice cap was not in balance with
the shape underneath," said Pascal Sirguey, a research scientist
at the university and project leader for the research. "The ice
eroded and changed a lot over the past 20 years," Sirguey told
LiveScience's OurAmazingPlanet. "It's like when cookies crumble."
[ Video:
New Zealand's Tallest Mountain Shorter Than Thought ]

Sirguey and his collaborators first discovered their country's
most famous peak had shrunk when they were building a digital
elevation model of a nearby glacier. "That model, no matter what
we did, didn't match the published elevation [of Aoraki/Mount
Cook]," Sirguey said. "When you compare photos from then and now,
it is also obvious, but no one had really noticed the change."

The team double-checked their measurements by climbing the
mountain on Nov. 23, 2013, and measuring its height with GPS receivers,
though they didn't ascend to the very top. Instead, they verified
the height a few meters from the summit. A trigonometric survey —
similar to the map-making done in the 1800s — also confirmed the
height from lower elevations on Aoraki/Mount Cook.

The indigenous Maori people of New Zealand, and the Ngãi Tahu
tribe in particular, consider the mountain to be an ancestor
and sacred. Stepping on the peak's highest point violates the
mountain's sacred status (a status which is also protected by New
Zealand's Department of Conservation). The research team also
presented their results to the Ngãi Tahu tribe before publicly
releasing the new height, Sirguey said.

And there is no reason to worry that Aoraki/Mount Cook will lose
its place as New Zealand's tallest peak in the near future. It's
still 75 feet (23 m) ahead of the second-place holder,
Rarakiroa/Mount Tasman, and is
growing about 0.4 inches (10 millimeters) every year thanks
to grinding tectonic plates underneath New Zealand.